engine ventilation

[johnvb1014]

Just completed a cruise with our Albin 27 where a lack of engine compartment ventilation was, I think, solved. I know there have been previous posts on this subject, but ones that seemed, to me, inconclusive. So here it is. After a long first day (14 hrs cruising) we entered a marina, shut down the engine, and when we were told we had to move there was nothing from the solenoid. As I understand it, high temperature means higher resistance, and insufficient voltage for the solenoid to engage. We waited until things cooled and then started the engine and moved.

But in considering engine compartment cooling, the arrangement of louvered vents seemed to make no sense. On each side there were two, with the forward ones facing aft and the aft ones facing forward. Since these connect to a common space it seemed to make no sense on how they would eliminate heat from the engine compartment.

We changed these so on one side both were both facing forward the on the other side both were facing aft, with the idea that this would produce a cross flow and allow heat to escape from the engine compartment. Indeed, after this when under way you could feel heat escaping from one side of the boat, depending on the wind orientation. We have starboard side facing forward and port facing aft. Heading into the wind results in port exhaust and with a following wind the starboard exhausts. Solenoid problem solved.

Interestingly, when we entered the next harbor, there was another Albin 27 with vents exactly as mine were originally. I don't know if Albin installed all of these in this orientation, but my recent experience convinces me that if you want to eliminate heat from the engine compartment, the vents should be as I have described.

John VB

[Jay Knoll]

John

That makes sense!

As a potential owner of a 27FC I'll have to check out how they are installed on the boat I'm looking at. Does the forward facing set of louvers pick up spray and get water inside the vessel?

Jay

[johnvb1014]

Jay

We did not experience any problems, but were not really in any heavy weather. I suspect we would get some, but any should drain down around the holding tank or water tank and into the bilge.

John

[don123]

The factory vent installation on my 27FC made perfect sense to me - The forward pair scoop air in and the aft pair vent it back out when the boat is underway

The early 27's with the 4 cylinder 4D61 had smaller vents than the later 6 cylinder models, so I did cut the holes larger and install 4 of the later model larger vents in my early model (1984) boat

I really doubt the solenoid problem on your boat was caused by excessive temperature - The solenoid *should* work fine even if it's really hot, assuming it's a good solenoid

Don

[JFOkie]

John,

I agree with Don regarding the solenoid, heat shouldn't impact it's operation; I would replace it and see what happens.

The ventilation of the engine compartment is interesting....I hate to admit that I don't know how my vents are aligned and which direction hey face. I have a 1987 27FC with a 78hp Nissan and will have to take a look and see how e vents are set up.

Replacing the solenoid isn't a very difficult project, just make sure you disconnect the negative wire on the battery.

Good luck.
John
"Nirvana"

[N4QC]

Heat in the engine room has its limits:

140 F for equipment
120 F for personnel
113 F for air intake
104 F for diesel fuel (temp of fuel)

Check out the following links on ventilation discussions…

http://www.yanmarhelp.com/i_vent.htm

viewtopic.php?p=6044&highlight=#6044


Suspect that heat in the engine room may have impacted the starter relay rather than the solenoid…

Have fun,